code: def test_empty(self):
      self.assertEqual(len(self.cs), 0)
      self.assertEqual(list(self.cs), [])
  
file_path: MONAI/tests/test_component_store.py
imports: from __future__ import annotations
  import unittest
  from monai.utils import ComponentStore
label_desc: Use image node_id 2 for calling the TestComponentStore obj's underlying member method code with example usage: obj.test_empty() without return types